I found an example how to implement Java SSLEngine here. Unfortunately the source code of the server is not complete. Do you know where I can find the complete source code from the tutorial?
Searching for an SSLEngine implementation myself, I started writing my own one, which I shared on Github. It involves an SSL/TLS server and client, and also a Demo class containing a running example. I would be glad if you take a look and even more if you provide feedback about possible bugs or better implementation.
Also feel free to check a post I uploaded on my (really newly created!) blog, where I collected various information about SSL/TLS. :)